Submarine signal fuze



ug- 7, 1962 K. L. BAKER ETAL SUBMARlNE SIGNAL FUZE 5 Sheets-Sheet 1 Filed Feb. l0, 1955 Aug. 7, 1962 K. L. BAKER ETAL 3,048,111

SUBMARLNE SIGNAL FUzE Filed Feb. 1o, 1955 3 Sheets-Sheet 2 INVENToRs K. L. BAKER T. C. SMITH L. A. PECHMANN ATTORNEYS Aug. 7, 1962 K. L. BAKER ETAL 3,048,111

SUBMARLNE SIGNAL FUzE Filed Feb. lo, 1955 s sheets-sheet s F l G. 5.

INVENTORS K. L. BAKER 59 T. c. SMITH 21A. PECHMANN ATTORNEYS Siill Patented Aug. 7, 1962 3,048,111 SUBMAE SHGNAL FUZE Kenneth L. Baker, College Park, Md., and Thomas C.

Smith, Poughkeepsie, and Louis A. Peehinann, Millbrook, NX., assignors, by direct and mesne assignments, to the United States of America as represented by the Secretary of the Navy Filed Feb. 10, 1953, Ser. No. 336,144 7 Claims. (Cl. IGZ-'70) The present invention relates to an arming and tiring mechanism for pyrotechnic signals adapted to be released under water and, in particular, to an arming and firing mechanism for pyrotechnic signals which are launched by a submerged submarine whereby intelligence may be conveyed to observers above the surface of the Water. The intelligence may be conveyed by a dye type marker released on the surface of the water, by smoke and/ or flame, or by a ilare type device launched into the air.

Devices of this type which have been used heretofore have been constructed in such a way that premature functioning of the signal has caused serious injury to persons handling the same. A careful study of prior art devices `and the arrangement through which these devices are launched from a submarine has indicated that the firing arrangement of the signal has not proven entirely satisfactory. Furthermore, the signal and fuze have not been suiciently safe to withstand sudden jars or bumps while being handled outside the launching means.

Accordingly, an object of this invention is to provide an arming mechanism for the signal which is actuated by means which are unique to the launching and surfacing of the signal.

A further object of the disclosure is to provide means operable from within and near to the end of the launching tube whereby the arming mechanism of the signal is released to function. By means of such an arrangement, a premature `operation activation of the signal or intelligence medium is prevented until the device is clear of the launching means aixed to the submarine hull.

A still further object of the invention is to provide an arming and firing mechanism for a signal of the described type which is operable through progressive steps and actuated by changing pressures of the water medium through which it is launched, and since it will of necessity be launched only from a submerged submarine, the steps are responsive first to a relatively high hydraulic pressure, followed by a relatively low hydraulic pressure. In this way, premature actuation of the signal by careless handling outside of the launching means is prevented.

It is a requisite of all such signal devices that the intelligence be released at the surface of the water and, accordingly, it is essential that the signal is positively buoyant. When the signal has reached the surface of the tbody of water into which it was launched, the relatively low hydraulic pressure step is satisfied and the arming and firing steps then are completed.

The present day submarine is designed to operate at far greater depths than have been possible heretofore. Accordingly, a still further object of the invention is to provide an arming and :firing mechanism for a signal which is rugged enough to withstand launching into the zone of high hydraulic pressure present at the greater depths at which the modern submarine may operate. Furthermore, the mechanism must be suthciently delicate to bring about proper functioning at the relatively low hydraulic pressures resulting from operation of the submarine in shallow water.

'I'he novel features of the signal device according to the present invention include a long guide shoe adapted to lit within the launching tube and bridge the water pulsing connection thereto whereby the actual launching is accomplished. Another novel feature of the device includes a locking device arranged on the signal body and interengaging the guide shoe to prevent the release of the same before the device is placed in the launching tube. A further novel feature of the device includes an arming and firing means operable only in response to the predetermined sequence of hydraulic pressure conditions to which the signal is subjected after being launched.

A still further novel feature of the signal device is the provision of an out-of-line firing arrangement whereby the firing charge is not placed in line with the firing pin until the high hydraulic pressure condition has been met.

- Other features of the signal device include a pressure responsive water inlet valve which controls the flow of water to within the body of the device, and a latch arrangement whereby movement of the mechanism within the body of the device due to jars, jolts or rough handling is prevented.

Other objects and many of the attendant advantages of this invention will be readily appreciated as the same becomes better understood by reference to the following detailed description when considered in connection with the accompanying drawings wherein:

FIG. l is an elevational view of the device of the present invention illustrating a pyrotechnic signal attached thereto;

FIG. 2 is a horizontal sectional view of the device of the present invention illustrating a fragmentary portion of the pyrotechnic signal and the launching tube, the device being shown in a safe or unarmed condition;

FIG. 3 is a view similar to FIG. 2 illustrating the device in an armed condition;

FIG. 4 is an end elevational view of the device of FIG. 2;

FIG. 5 is a vertical sectional view taken on the line 5-5 of FIG. 2; and

FIG. 6 is a fragmentary elevation view to the sector plate and the tiring pin latch carried thereby.

Referring now to the drawings for a more complete understanding of the invention and more particularly to FIGS. l and 2 thereof, the numeral 10 generally indicates the fuze mechanism of the present invention, 11

' indicates a conventional pyrotechnic intelligence conveying or signalling device and 12 indicates a fragmentary portion of a submarine launching tube.

The fuze device is contained within a hollow cylindrical body 13 adapted for mounting on, or partially within, the enclosure shell 14 of the pyrotechnic signal 1l, the device 10 and signal device 11 being secured together in any suitable manner such, for example, as threading the p-arts together as indicated by the reference character 15, a sealing gasket 16 being disposed between the opened end of the shell 14 and a. shoulder 17 formed on the body 10. The hollow body 13 is divided generally into two chambers 18 and 19 by a bulkhead or partition 20. The outer end wall 21 of the body 13 is formed with a centrally located boss 22 having an inwardly extending opening 22a adapted to receive one end of a reciprocating piston generally indicated -by the numeral 25. The bulkhead 20 carries a centrally located boss 23 having a through .opening 24 adapted to receive the other end of piston 2S. The piston 25 comprises a rod or sleeve 26 and a ring pin 27 which are in axial alignment and detachably locked together by a ball type latch actuated by spring 30 in a manner to be described in detail hereinafter. The ball type latch comprises a pair of locking balls 28 respectively disposed in a pair of diametrically arranged openings 29' formed in the rod or sleeve 26. As shown more clearly on FIG. l the balls 28 are disposed within an annular groove 31 formed in the tiring pin 27 and maintained in engagement therewith by a sleeve or bushing 32 secured to the boss 23 as at 33. The sleeve is provided at one end thereof with an annular recess 34 the purpose of which will become more apparent as the description proceeds. The rod-like portion 26 of the reciprocating piston is arranged within chamber 19 of the body 13 and is secured to a ange 35 as at 36. One end of a flexible bellows 37 is attached to the iiange 35 in any suitable manner such, for example, as welding the part together, 'While the other end of the bellows is se cured to bulkhead 20 as at 38.

In order that the `bellows 37 may be extended at atmospheric pressure, a spring 39 is arranged within the bellows and extends between the collar 50 and the flange 35, the spring being arranged about the piston 25, boss 23 and sleeve 32. It will be understood, however, that by this arrangement the spring and bellows exert a force against the underside of flange 35 equivalent to a force of -11 p.s.i. hydraulic pressure in chamber 19 available via passage or port 41 formed in end wall 21, FIGS. 2 and 3.

Movement of the piston 25 due to jars, bumps, or rough handling is prevented by the interengagement of an annular groove 42 formed in the rod 26 of the piston 25 and a locking dog 43 arranged within boss 22 and extending perpendicular to the line of movement of the piston. The outer end of the dog 43 extends to the exterior of the body 13 and is tted with a spring loaded valve arrangement generally indicated bythe reference character 44 which is responsive to the hydraulic pressure of the surrounding water prevailing outside of the body 13 when the signal is launched in a body of water.

The spring loaded valve 44 is disposed Within a well 45 formed in boss 22 and comprises a valve head 46 integrally formed on the locking dog 43, the head 46 being in sealed engagement with a valve seat 47 arranged within the boss 22 and composed of any material suitable for the purpose such, for example, as rubber or the like. The valve head 46 has formed thereon a sleeve 48 having a flange 49 arranged on one end thereof in abutting engagement with the wall defining the well 45 and a shoe generally indicated by the numeral 51. The sleeve 4S is provided with a centrally disposed bore 52 having a spring 53 arranged therein, one end of the spring being in engagement with the shoe 51, the other end thereof being in engagement with the valve head 46. As more clearly shown on FIG. 2 a spring 54 is disposed about the sleeve 4S, one end of the spring being in engagement with the flange 49, the other end thereof being in engagement with valve seat 47. The sleeve 48 is provided with a plurality of transverse ports or openings 55.

The valve 44 is maintained in a normally closed position by the guide shoe 51, movement of the shoe being prevented by the latch 56, and movement of the latch being prevented by the safety pin 40. However, as the device is placed within .the launching tube, the safety pin 40 is removed from the latch member and the shoe is engaged in the T-shaped slot 57 formed in the tube and thus the shoe remains in engagement with the valve 44 to maintain the valve in a closed position until the device leaves the tube whereupon the latch is tripped and the shoe moves tol the release position (FIG. 3). The valve arrangement is operable in response to a predetermined hydraulic pressure after it is freed to move by the launching mechanism in a manner which will now be explained.

As more clearly shown in FIG. 4, the T-shaped slot comprises a broad portion 58 and a restricted portion 59 bordering thereon. When the signal device 11 is placed within the launching tube 12 the latch 56 extends into the stem or restricted portion 59 of the slot 57 and the guide shoe 51 extends into the flat or broad portion 58 thereof. The fiat portion 58 of the slot is continuous throughout the length of the launching tube but the stem portion 59 stops short of the outer end of the tube.

Thus when the device is placed in the launching tube with the shoe disposed within the portion 58 of the slot 57, the guide shoe 57 will maintain the valve 44 in a closed position regardless of the position of the latch 56. When the device is not in the launching tube, the guide shoe 51 is prevented from rotation about the shaft 61 -by a pin 62 disposed in a slot 80 formed in the latch 56 and extending from the latch through the guide shoe 51 and into a recess 63 in the body 13. This pin may be removed only by the rotation of latch 56 about the shaft 61, however, rotation of the latch and removal of the pin is prevented by a safety pin 40 extending through the latch and shaft.

Axially remote from the detent in the rod-like portion of the piston 25, and arranged within the chamber `18, is a rotatable arming device generally indicated by the reference character 6i) by which the tiring charge is brought into line with a striker 70 formed on end of the ring pin 27. The arming device is best shown in FIG. 5 and comprises a shaft 64 upon which a normally locked Sector plate 65 is rotatably supported, the plate being adapted to be rotated in a clockwise direction under the urging of a spring 66 when released. Arranged on the rotatable sector plate 65 is a latch 67, including a `boss 63 and a holder 69 for the primer, delay and relay element 71 arranged in a sleeve 72 formed on and carried by the sector plate 65.

The boss 68 is provided with a centrally disposed bore 73 having an end wall 74 formed on one end thereof, the wall and a portion of the boss 66 being provided with a slot 75, one end of which is open as at 76, FGS. 5 and 6. yAs more clearly shown in FIG. 6 the boss 68 has formed therein a slot 77 bordering on the slot 75 and of greater Width than the slot 75, one end of the slot 77 being open as at 78 and restricted as at 79.

As more clearly shown on FIG. 2 the shaft 81 of the tiring pin 27 is disposed within the slot 75 and the collar on disc 82 formed thereon in disposed within the bore 73 in engagement with the end wall 74 and alignment with the restricted slot 75. By this arrangement the sector plate is in a locked condition until the firing pin is removed sufficiently to cause alignment of the disc with the slot 77 and thus releasing the sector plate for movement from an initial safe position to an armed position by the arming spring 66.

The shaft 64 for rotatably supporting the sector plate 65 is secured to the bulkhead 20 in any suitable manner preferably by threading one end S4 thereof into a suitable opening 35 formed in tbe bulkhead, the shaft being provided with wrench engaging surface 86 whereby a wrench may be attached thereto for threading the end 34 into the opening 85. The shaft 64 is disposed within a ibore 87 formed in the sector plate 65 and a bore 88 formed within an ear 89 carried by the sleeve 72. By this arrangement the sector plate is supported by the shaft 64 for rotative movement.

As more clearly shown on FIG. 4 the shaft 61 is supported by a pair of mutually spaced ears 91 formed on the casing, the shoe being pivotally mounted ou the shaft by a pair of ears 92 formed thereon and disposed at a right angle with respect to the shoe. It will be noted that the latch 56 is keyed on the shaft 61 and disposed between the ears 92 and in abutting engagement with the offset portion 93 of the shoe. It will be understood that the latch and shoe are supported by the shaft 61 for rotative movement. However, rotative movement of the latch 56 and shoe 51 is prevented by means of the safety pin 40 and rotation thereof will not occur until the safety pin is removed and the latch 56 is tripped.

As more clearly shown on FGS. 2 and 3 a plug 94 closes the open end of the casing 13, the plug being threaded therein as at 95 and a sealing gasket 96 being disposed between the casing 13 and plug 94. The plug 94 has formed therein a centrally disposed recess or well 97 and a restricted recess 98 in communication therewith,

the recess being provided with a relatively thin wall 99 bordering on chamber 13, the wall 99 being in alignment with the combination primer, delay and relay element 71 when the sector plate has been rotated to an armed position, FIG. 3. It will be understood that a conventional pyrotechnic charge may lbe arranged in the well 97 and recess 9S, such, for example as an expellant charge or the like, the charge being indicated by the numeral 101. The charge 101 is adapted to be red by the element 71 in time delayed relation with respect to the firing of the element by the striker 70. The firing of the charge 101 by the element will not occur until after the signal has reached the surface of the body of water.

In order that the primer may be ignited, it is necessary that the chamber 18 be watertight and sealed off from chamber 19. This is accomplished elfectively by the aforesaid flexible bellows 37 sealed at one end to the bulkhead 20 and at the other end to the iiange 35 which as heretofore set forth is secured to the piston rod 26 as at 36.

In the operation of the device, the signal and fuze assembly is placed in the launching tube and the pin 4@ is removed. Since the guide shoe is tted snugly within the portion 58 of the T-shaped slot and the overhanging end of latch 56 is fitted in the restricted portion 5@ of the aforesaid slot formed in the wall of the launching tube, the shoe and latch are held immobilized. The spring 53 is held compressed by the shoe 51 which overcomes the force of spring 54 thereby effecting sealing of valve head 46 with respect to the seat 47. It will be understood, however, that after the lbreech of the launching tube is closed a manually operated plunger or a water jet under a pressure of at least 50 p.s.i. greater than the pressure existing in the tube due to the submerged depth of the submarine is utilized to eject the signal and `fuze assembly from the tube.

As has been heretofore mentioned, the stem portion 59 of the T-shaped slot terminates prior to the end of the launching tube while the ilat portion 58 of the slot is continuous for the entire length of the tube. As the signal fuze passes outwardly through the tube, the overhanging portion of the latch 56 engages the closed end of slot 59 whereupon the latch is rotated in a clockwise direction at the termination of the restricted portion 59 of the slot 57. As the latch rotates about its axis 61, the pin 62 is withdrawn from recess 63 formed in the body of the device. When this occurs the guide shoe 51 is freed for rotation about the axis 61. As the device moves beyond the discharge end of launching tube, the guide shoe is moved in a clockwise direction by spring 53 and the external valve means 44 arranged on one end of the locking dog 43 is freed for subsequent movement under the control of spring 54 and the external pressure.

Since the signal 11 has a positive buoyancy it will iloat to the surface of the water after leaving the launching tube. It will be understood, however, that at depths whereupon the pressure of the surrounding water is in excess of approximately 50 p.s.i., the force exerted by the spring 54 will be overcome by the pressure of the surrounding water and thus the valve means 44 will be held closed by the external water pressure. As the device approaches the surface of the body of Water the external water pressure decreases to a value less than 50 p.s.i. When this occurs the valve means begins to open under the influence of the force exerted thereon by spring 54. Accordingly, water is admitted by way of well 45, transverse ports 5S and thence through a passage 41 to the interior of chamber 19 whereupon a hydraulic pressure is built up within the chamber and directed against the ange 35 of the bellows arrangement. When valve means 44 is moved to an open position by the spring 54, the locking dog 43 is moved sufficiently to be withdrawn from the groove 42 formed in the portion 26 of the tiring pin assembly and thus releasing the piston for movement in response to a predetermined hydraulic pressure which thereafter builds up in chamber 19.

As heretofore mentioned, the opening of the valve means 44 began when an external pressure of about 50 p.s.i. is attained, or when the device is substantially to feet below the surface of the water. When the valve means 44 becomes fully opened, the locking dog 43 is withdrawn from the path of travel of the piston 25.

Although the signal may be launched at depths in excess of 110 to 115 feet it may also be launched at minimum depths of about 25 feet and still function satisfactorily. At the aforesaid shallow depths, the valve 44 will open immediately upon the device leaving the launching tube and, accordingly, the chamber 19 will be exposed to substantially 11 p.s.i. of hydraulic pressure. As heretofore mentioned, spring 39 and bellows 37 exert an eective force of about 5 to ll p.s.i. hydraulic pressure against the flange 35, the flange and piston are moved to the right in response to the hydraulic pressure prevailing in chamber 19. The two portions 26 and 27 of the piston move together by reason of the aforesaid ball locking arrangement.

As the piston continues to move the flanged portion 82 thereof adjacent the striker 7@ is moved into alignment with the slot 77 whereupon the sector plate 65 is released for rotation to an armed position by the spring 66. Upon rotation of the sector plate 65 clockwise about the shaft 64 the holder or sleeve 72 containing the primer charge 71 is brought into line with the tiring pin.

As the signal approaches the surface of the body of water, the external hydraulic pressure falls to a value of approximately O p.s.i. and accordingly, the pressure within chamber 19 likewise falls. At substantially the same time, the elfective force of the spring 39 and the bellows 37 is exerted against the flange 35 whereupon movement of the piston 25 is reversed and thus the piston is moved to the left, the two portions 26-27 thereof remaining locked together by the aforesaid ball type latch. It will be understood that a bushing 32 is fabricated of a tough steel in order to avoid Brinelling by the rolling of the balls 2S of the latch thereover. As the balls 28 of the latch approach the enlarged or recessed portion 34 of the bushing 32 they move outwardly. When the balls have moved sufficiently to be in alignment with the recess 34 of bushing 32, the firing pin 27 is released from the rodlike portion 26 of the piston. When this occurs, the firing pin is forcible moved forwardly under the influence of spring 39 and thus the striker ill is forcibly driven into ring engagement with the combination primer, delay and relay element 71 resulting in the deagration and detonation of that element which causes the rupture of the thin wall 99 leading into the main body 14 of the pyrotechm'c signal and firing of the charge 101.

Having described the mechanical arrangement and mode of operation of a device constructed according to this invention, attention is called to the following features speciiic and unique to the device.

Through the mechanical means whereby the guide shoe 51 is held adjacent to the body of the device and the combined valve arrangement 44 and dog 43 is held in a position within an annular groove formed in the rod-like portion of piston 26, the device is held in an unarmed state at all times until the guide shoe is released for rotation.

Through the mechanical means whereby the delay element 71 is held out of alignment with respect to the tiring pin 27, the device being held in an unarmed state at all times until the ange 35 is subjected to a hydraulically derived force exerted thereon by the flexible bellows 37.

Through the mechanical means whereby the piston 25 must be moved first in one direction to bring the delay element 71 in alignment with the fir-ing pin 27 and then in the opposite direction for a predetermined amount, or distance, before the firing pin 27 is released, a distinct sequence of operation is established and the device is held in an unarmed condition until such a sequence of 75 operation is completed.

Through the unique and distinct sequence of pressures required to move the firing pin 27 and the delay element 71 into firing position, a premature firing of the signal within the launching tube is prevented. Conversely, since the water entry valve 44 is held closed at all times while the device is in the launching tube, the device may be safety withdrawn from the launching tube breech if the device should not be expelled from the tube by the normal launching procedure.

Through the use of an elongated guide shoe 51 of suflicient length to breach the inlet for entry of the iluid medium by means of which ,the device is ejected from the launching tube, premature opening of the valve arrangement 44 while the device is within the launching tube is prevented.

Through the use of a delay element 7l having known pyrotechnic characteristics, a time factor is introduced just prior to the actual ring of the signal suicient t0 enable the signal to come to a state of rest on the surface of the water. The element 71 also gives sufficient delay such that initiation of the delay element may normally occur far enough below the surface of the body of water to give reliable initiation under normal conditions.

Through the use of a frangible seal 99 the arming and tiring mechanism is maintained `completely enclosed within the body 13 at all times whether the same be mounted in the signal body proper or stored or being carried separately.

Obviously many modifications and variations of the present invention are possible in the light of the above teachings. It is therefore to be understood that within the scope of the appended claims the invention may be practiced otherwise than as specifically described.

What is claimed as new and desired to be secured by Letters Patent in the United States is:

l. A device for firing a pyrotechnic charge comprising a casing having a pressure chamber therein, normally locked firing means axially arranged within said casing, arming means axially arranged within said casing releasably secured to said tiring means for rotation from an initial safe `axial position to an armed axial position when released, means on said firing means for releasing the arming means for rotation from said initial safe position to said armed position when the firing means has been moved a predetermined amount, means secured to the firing means and disposed within said pressure chamber for moving the firing means said predetermined amount in response to a predetermined pressure applied thereto, pressure controlled valve means on said `casing for admitting the pressure into said chamber, pyrotechnic initiating means arranged within said arming means and movable into alignment with the tiring means as the arming means is moved to said armed position, means on the firing means for forcibly driving the firing means into firing engagement with said initiating means as the firing means is released thereby tto ire the pyrotechnic charge, and means for releasing the tiring means when the pressure in the chamber has been reduced to a predetermined value.

2. A device for firing an expellant ycharge comprising a casing having a pressure chamber therein, normally locked arming means axially arranged Within said casing and movable from an initial safe axial position to an Iarmed axial position when released, normally locked firing means axially arranged within said casing, a protuberance formed on said arming means, protuberance engaging means on said ring means for maintaining the arming means in said initial safe position and for releasing the arming means for movement to said armed position as the engaging means is moved out of engagement with said protuberance, pressure responsive means disposed Within said chamber for moving said firing means an amount sufficient to cause said engaging means to be disengaged from said protuberance in response to a predetermined pressure applied thereto, pressure actuated valve means, means including a valve arranged on the casing in communication with said lchamber for admitting said pressure into the chamber, a pyrotechnic element disposed within the arming means and movable into alignment with the firing means as the arming means is moved to said armed position, means on the tiring means for forcibly driving the ring means into firing engagement with said pyrotechnic element as the ring means is released thereby to fire the expellant charge, and means including a pair of detents for releasing the tiring means when the pressure in the `chamber has been reduced to a predetermined value.

3. A fuze suitable for use with an ejector type submarine signal adapted to be launched in a body of water and comprising a casing having a pressure chamber therein, pressure responsive means arranged within said casing in communication with said chamber and the surrounding water for `admitting pressure into the chamber as the signal is launched and the pressure of the water has been reduced to a predetermined value, normally locked rotatable arming means axially arranged within said casing and rotatable from an initial safe axial position to an armed axial position when released, ring means for locking the arming means in said initial safe position and for releasing the arming means for rotation to said armed position when the firing means is moved a predetermined amount, means secured to said tiring means and actuated in response to the pressure within said chamber for moving the ring means said predetermined amount, means on said arming means for rotating the arming means to said armed position as the arming means is released, a pyrotechnic element disposed within the arming means and movable into alignment with the firing means as the arming means is rotated to an armed position, means operatively connected to said firing means for releasing the firing means when the pressure in said chamber has been reduced to a predetermined value, and resilient means operatively connected to said tiring means for forcibly driving the firing means into tiring engagement with said pyrotechnic element as the firing means is released thereby to lire the element.

4. A fuze suitable for use with an ejector type submarine signal adapted to be launched in a body of Water beneath the surface thereof and comprising a casing having a pressure chamber therein, normally sealed valve means arranged within said casing in communication with said chamber and the surrounding water, means operatively connected to said valve for unsealing the valve when the pressure of the surrounding Water has been reduced to a predetermined value resulting from the approach of the signal toward the surface of said water, means for admitting pressure into said chamber as the valve is unsealed, normally locked rotatable arming means axially arranged within the casing and rotatable from an initial safe axial position to an armed axial position when released, normally locked firing means arranged within said casing, means on said firing means for locking the arming means in said initial safe position and for releasing the arming means for rotation to said armed position when the firing means is moved a predetermined amount, a pressure responsive device secured to said firing means and actuated in response to the pressure within said chamber for moving the liring means said predetermined amount, a resilient element operatively connected to said arming means for rotating the arming means to said armed position as the arming means is released, a pyrotechnic element disposed Within the arming means and movable into alignment with said ring means as the arming means is rotated to an armed position, means in engagement with said pressure responsive device for releasing the firing means when the pressure within the chamber and on said pressure responsive device has been reduced to a predetermined value, and means operatively connected to said tiring means for forcibly driving the firing means into firing engagement with the pyrotechnic element as the tiring means is released thereby to fire the element.

5. A fuze suitable -for use with an ejector type submarine signal adapted to be launched in a body of Water beneath the surface thereof and comprising a casing, said casing having a pressure chamber formed therein, valve means normally sealed to said casing in communication with said chamber and the surrounding water, means including a shoe in engagement With said valve means Afor maintaining the valve means sealed to the casing until the signal has been launched in the body of water, resilient means operatively connected to said valve means for unsealing the valve means when the pressure of the surrounding Water has been reduced to a predetermined value resulting from the approach of the signal toward the surface of said Water, port means in said casing for admitting pressure into said chamber as the valve means is unsealed, normally locked ar-ming means arranged within the casing and rotatable to an armed position when released, normally locked firing means arranged Within the casing, means on said ring means lfor locking the arming means in an initial safe position and -for releasing the -arming means for rotation to said -armed position when the firing means is moved a predetermined amount, a pressure responsive device secured to said ring means and actuated in response to the pressure Within said chamber vfor moving the firing means said predetermined amount, a resilient element operatively connected to said arming means for rotating the 'arming means to said armed position as the arming means is released, a pyrotechnic element disposed within the arming means and movable into alignment with said firing -means as the arming means is rotated to said armed position, means including a pair of detents releasably connected to said firing means for releasing the firing means when the pressure within said chamber and the pressure on said pressure responsive device has been reduced to a predetermined value as the signal approaches the surface of the Water, and means operatively connected to -said firing means for forcibly driving the firing means into firing engagement with the pyrotechnic element as the firing means is released thereby to lire the element.

6. A fuze suitable for use with an ejector type swbmarine signal adapted to be launched in a body of water beneath the surface thereof and comprising a casing having a pressure chamber therein, valve means normally sealed to said casing in communication with said chamber and the surrounding Water, a normally locked shoe in egagement -With said valve means for maintaining the valve means sealed to the casing, means lin engagement with said shoe for releasing the valve means as the signal is Ilaunched in said body of water, means operatively connected to said valve means for unsealing the valve when the pressure of the surrounding Water has been reduced =to a predetermined value resulting from the approach of the signal toward the surface of said Water, port means in the casing in communication fwith the surrounding Water as the valve means is unsealed for admitting pressure into said chamber, normally locked arming means arranged within the casing and rotatable to an armed position when released, normally locked firing means arranged Within the casing, means including a collar on said ring means in engagement with said arming means for locking lthe arm-ing means in an initial safe position and adapted to release the arming means for rotation to said armed position fwhen the ring means is moved a predetermined amount sufficient to disengage the collar Ifrom said arming means, a pressure responsive device disposed Within said chamber and secured to said ring means for moving the firing means said predetermined amount in response to a predetermined pressure applied thereto, a resilient element loperatively connected to said arming means for rotating the arming means to said armed position as the arming means is released, .a pyro-technic element disposed Within the arming means and movable into alignment With said ring means as the arming means is rotated to said armed position, means secured to said casing for rotatably supporting said arming means, m-eans including a pair of locking devices releasably connected to said :firing means for releasing the firing means when the pressure within said chamber and the pressure on the pressure responsve device has been reduced to a predetermined v-alue eiective as the signal approaches the surface of the Water, and means operatively connected to the ring means 4for yforcibly `driving the firing means into firing engagement with the pyrotechnic element as the iiring means is released thereby to lire the element.

7. A fuze suitable for use with an ejector type submarine signal adapted to be launched in a body of Water beneath the surface thereof and comprising a casing having a pressure chamber therein, valve means normally sealed to said casing in communication With said chamber land the surrounding Water, means including a shoe in engagement -With said valve means for main-taining the valve means sealed to said casing until the signal has been launched in the `body of Water, means operatively connected to said valve means for unsealing the valve means when the pressure of the surrounding Water has been reduced to a predetermined Value effective when the signal device reaches a predetermined depth Within the Water, por-t mea-ns in said casing `for admitting pressure into the chamber as the valve is unsealed, a sleeve releasably locked Within said casing, means on said valve means -for releasing said sleeve for sliding movement, within said casing as the valve means is unsealed, tiring means releasably locked to said sleeve, means including a pair of locking devices for releasably locking the tiring means -to the sleeve as the firing means and sleeve are moved a predetermined amount in one direction, a pressure responsive device secured .to said sleeve and actuated in response to the initial pressure within the chamber for moving the firing means and sleeve said predetermined amount in one direction, normally locked arming means arranged Within `the casing and rotatable from an initial safe position to an armed position when released, means on said tiring means for locking the arming means in said initial safe position and 'for releasing the arming means for rotation to said armed position as the firing means .and sleeve are moved said predetermined amount in one direction, means for rotating said arming means to said armed position, a pyrotechnic element disposed within the arming means and movable into alignment with said ring means as the arming means is rotated to said armed position, locking device releasing means in the casing for releasing said ring means `from the sleeve as the ring means and sleeve are moved a predetermined amount in the other direction elective as the pressure Within the chamber has been reduced to a predetermined value, and means operatively connected to the tiring means for forcibly driving the 4tiring means into ring engagement with said pyrotechnic element as said tiring means is released thereby to fire said element.

References Cited in the tile of this patent UNITED STATES PATENTS 2,505,000 Moore Apr. 25, 1950 2,513,185 Lauritsen June 27, 1950 2,764,090 Turlay Sept. 25, 1956 FOREIGN PATENTS 257,335 Great Britain Aug. 27, 1926 

